Most drills are either manually operated, such as illustrated in FIG. 1, or power operated, such as illustrated in FIG. 2, and nearly all include an assembly D to hold a drill bit B to the handle H of the drill. This assembly generally includes a chuck C, a collar E and a jaw J into which the shank S of the drill bit fits. The jaw J is opened to receive the drill bit shank, and is then tightly closed onto that drill bit shank to attach the drill bit to the handle.
The jaws of the drill are opened and closed using a chuck key K, such as is illustrated in FIG. 3, that includes a bevel gear G and a handle CH. The handle is often connected to the bevel gear by a shank CS. The bevel gear G is inserted into receiving holes RH on the collar C and rotated to open and close the jaws of the drill.
The inventor has found that there are instances in which the jaws of the drill are either undertightened or overtightened and further instances when it is difficult or onerous to operate the drill jaws using a chuck key such as shown in FIG. 3.
For example, if the jaws are undertightened, the drill bit may not be securely fastened to the handle, which may give rise to a dangerous situation at worst, and to an inaccurate work operation at best. On the other hand, however, if the drill jaws are overtightened, time and effort is wasted and various elements of the drill may be subjected to unnecessary wear.
Still further, the chuck key such as illustrated in FIG. 3, must be turned one way to close the jaws, and the opposite direction to open the jaws. The inventor has also found that, in some situations, it is cumbersome or annoying to operate the chuck key in one direction or the other. This situation can occur when the drill is being used in a tight or special location or in a special orientation. Still further, keys such as shown in FIG. 3 are small and are prone to becoming lost or misplaced.
Accordingly, there is a need for a drill chuck key that is easy to use, and need be turned in only one manner to either tighten or loosen the jaws of a drill, yet will not be prone to overtightening or undertightening the drill jaws.